• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2007년도 추계학술발표회
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• pp.161-167
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• 2007

실습선의 선교가 운항의 안전성과 효율적인 항해실습교육을 동시에 담보할 수 있도록 설계 되었는지 검토하였던 연구는 전무한 상태이다. 이에 본 연구는 국내 실습선의 선교를 주항해선교와 실습선교의 배치형태에 따라 전후형 선교배치, 상하형 선교배치, 단일형 선교배치의 3가지 배치형태로 분류하였다. 또한 설문조사를 통하여 실습선 선교 배치형태에 따라 항해실습교육의 운영형태가 서로 어떻게 달라지는지 검토하였고, 운항과 항해실습교육을 병행하는 데 있어 야기되는 장 ${\cdot}$ 단점을 도출하였다. 이를 바탕으로 운항의 안전성을 확보하고 효율적인 항해실습교육을 위해 새로운 형태의 실습선 선교 개선 모델을 제시하였다.

• 해양환경안전학회지
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• 제14권2호
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• pp.169-175
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• 2008

지금까지 실습선의 선교가 운항의 안전성과 효율적인 항해실습교육을 동시에 담보할 수 있도록 설계되었는지 검토하였던 연구는 전무한 상태이다. 본 연구는 국내 실습선의 선교를 주항해선교와 실습선교의 배치형태에 따라 전후형 선교배치, 상하형 선교배치, 단일형 선교배치의 3가지 배치형태로 분류하였다. 또한 설문조사를 통하여 실습선 선교 배치형태에 따라 항해실습교육의 운영형태가 서로 어떻게 달라지는지 검토하였고, 운항과 항해실습교육을 병행하는 데 있어 야기되는 장 단점을 도출하였다. 이를 바탕으로 운항의 안전성을 확보하고 효율적인 항해실습교육을 위해 새로운 형태의 실습선 선교 개선 모델을 제시하였다.

• Structural Engineering and Mechanics
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• 제64권2호
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• pp.225-232
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• 2017

Leaning-type arch bridge is a new spatial structural system composed of two vertical arches and two leaning arches. So far there has been no contrast analysis of leaning type arch bridge with different systems. This paper focus on a parametric study of leaning type arch bridge with different systems to find the influential rules on structural forces and stability and to provide some reference for practical designs. The parametric analysis is conducted with different rise-to-span ratios and bending rigidities of arch ribs by comparing internal forces. The internal forces decline obviously with the increase of the rise-to-span ratio. The bending moments at the centers of the main arches and the leaning arches are sensitive to the bending rigidities of arch ribs. Parametric studies are also carried out with different structural systems and leaning angles of the leaning arch by comparing the static stability. The lateral stiffness of leaning-type arch bridge is less than the in-plan stiffness. Compared with the leaning-type arch bridge without thrust, the leaning-type arch bridge with thrust has a lower stability safety coefficient. The stability safety coefficient rises gradually with the increase of inclining angle of the leaning arch. This study shows that the rise-to-span ratio, bending rigidities of arch ribs, structural system and leaning angles of the leaning arch are all critical design parameters. Therefore, these parameters in unreasonable range should be avoided.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2002년도 추계학술대회 논문집(I)
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• pp.672-677
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• 2002

Railway bridge type has been mainly selected by a intersection of roads and rivers, and economy. Now a days, it is required that the bridge type is considered a harmony with circumstances, a beauty and an expression of symbol of regions because of the enlargement of bridge structures and the advance of people's consciousness level. So it is adopted arch bridge with fan type hanger for a outer beautiful sight and a symbol of development of regions as 80m intersection bridge of railway and former national road at pal hung bridge in jolla line lot 1. It is performed that an examination, a consultation, a design of member sections and a detail analysis of joint parts according to the basic design. It is also performed a dynamic analysis with design loads and train loads reflection on railway bridge characteristics and examined a safety and a propriety of design compare with a fatigue design and design rules.

• 대한전기학회논문지:전력기술부문A
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• 제53권11호
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• pp.619-623
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• 2004

We proposed the bridge type superconducting fault current limiter(SFCL) using switching operation of high-Tc superconducting(HTSC) thin film. The proposed bridge type SFCL consists of HTSC thin film, a diode bridge and a dc reactor. The controller for the operation of an interrupter is required in the conventional bridge type SFCL to prevent the continuous increase of fault current after a fault happens. On the other hand, the proposed bridge type SFCL can limit the fault current without the interrupter and the controller for its operation by the resistance generated when the gradually increased fault current exceeds HTSC thin film's critical current. We calculated the time when the gradually increased fault current started to be limited by the resistance generated in HTSC thin film after a fault happened and confirmed that it could be dependent on the amplitude of source voltage. The experimental results well agreed with the calculated ones from simulation.

• Journal of Power Electronics
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• 제16권6호
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• pp.2099-2108
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• 2016

The cascaded multilevel converter is widely adopted to medium/high voltage and high power electronic applications due to the small harmonic components of the output voltage and the facilitation of modularity. In this paper, the operation principle of a T-type H-bridge topology is investigated in detail, and a carrier phase shifted pulse width modulation (CPS-PWM) based control method is proposed for this topology. Taking a virtual five-level waveform achieved by a unipolar double frequency CPS-PWM as the output object, PWM signals of the T-type H-bridge can be obtained by reverse derivation according to its switching modes. In addition, a control method for the T-type H-bridge based cascaded multilevel converter is introduced. Then a single-phase T-type H-bridge cascaded multilevel static var generator (SVG) prototype is built, and a repetitive controller based compound current control strategy is designed with the DC-link voltage balancing control scheme analyzed. Finally, simulation and experimental results validate the correctness and feasibility of the proposed modulation method and control strategy for T-type H-bridge based cascaded multilevel converters.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2023년도 봄 학술논문 발표대회
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• pp.277-278
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• 2023

The need for maintenance of bridge infrastructure is increasing due to aging, and the cost of maintaining the infrastructure must be calculated for effective budget distribution. Therefore, in this study, representative defects according to bridge superstructure type are derived to calculate the cost for each repair method. First of all, the representative bridges, PSCI girder bridge, Rahmen bridge, Steel box girder bridge, and RC slab bridge, were selected as superstructures using BMS data, and repair methods for defects were presented. In addition, the cost of the repair method by superstructure type was compared. This result is expected to predict total maintenance costs in consideration of the maintenance cycle.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계학술발표회 논문집(I)
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• pp.194-197
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• 2006

This study represents results of fragility curve development for 4-span continuous bridge. 2 type bridge model is chosen frame type and 2-roller 1-hinge type. To research the response of bridge under earthquake excitation, Monte Carlo simulation is performed to study nonlinear dynamic analysis. For nonlinear time history analysis a set of 150 synthetic time histories were generated. Fragility curves in this study are represented by lognormal distribution functions with two parameters and developed as a function of PGA. Five damage states were defined to express the condition of damage based on the actual experimental damage data of bridge column. As a result of this research, the value of damage probability corresponding to each damage state were determined and frame type bridge are favorable under seismic event.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 춘계학술대회 논문집
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• pp.262-267
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• 2008

The type used mainly in present our country in the superstructure of the railway bridge including the high speed railway is classified by the box girder and the I-type girder, greatly. The box girder is mainly used by the high speed railway bridge, and the I-type girder is used mostly by general railway bridge style. In this study, according to current railway bridge design code, we execute design by the span length of each considered bridge form. Also we analyze the suitable girder height by the span length and calculate the construction costs. The comparative analysis of the structural efficiency is produced by the span length. From this study, it is exposed that the girder height by the span length is the biggest in box girder. Also it is evaluated that the construction costs of the box girder is higher than that of the I-type girder although there is a difference between more or less according to adopted construction method.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.451-457
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• 2008

The aim of the sturdy is for the development of Bridge plate installing on floor for SETPA Sliver line V. SEPTA train have pocket sliding door which is similar with domestic trains. typically In the USA railway market, Portable type and standing type bridge plate used, easily hiding the bridge plate in stowed position and convenience operation, Bridge plate installed on floor is designed. relative regulation Like CFR APTA, and EN, UIC is reviewed and compared.